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K3WE's avatar
K3WE
Explorer
Apr 11, 2014

Diff. lock-Because I've never seen it, it doesn't exist

A few weeks ago there was a short grumbly exchange about "positraction" and locking differentials...

For my entire 50+ years on a standard pickup truck a "locking differential" was this automatic, self-contained clutch thing IN the differential that would lock up IF one wheel started spinning...

...but lots of posters were saying that it's a switch up on the dash...Some posters were livid- "you're crazy, pickup trucks don't have these"...

I also had my doubts- but was also very aware of farm tractors with differential lock outs- and who am I to tell folks there's no switch on THEIR truck because there's no switch on mine...still, are they smoking something, or folks with some crazy drag racing modification???

Well today, I picked up my new truck (Toyota Tacoma) and I wanted a locking rear differential and sure enough...there's a switch on the dash that simply locks the differential!

I dunno- maybe it saves weight and is the modern way (and yeah- traction control systems are also doing the job of addressing wheel spin too...but that you need the lock out for slow speeds).

Anyway- I feel the need to apologize for all the things I THOUGHT...

By the way, can my truck pull a 32 ft travel trailer? :-)

26 Replies

  • GM has been using the G80 Eaton locker for years, maybe decades. It's an auto locker - no switch needed. One wheel slips, the diff locks, you get unstuck, it unlocks. Easy peasy. Much better than a limited slip/positraciton, IMHO.

    Only downside - it's not very tolerant of abuse. Lead-footed drivers tend to break them.
  • My F150 has an electronic locker. Pull the knob on the dash and the diff locks solid. But it's smart - it won't engage if you're going over 20MPH, and disengages once you hit 20MPH.
  • Fords have an optional switch, GMs are auto lockers (G80), RAM has a less useful "limited slip".
  • Lock outs are nice, because the tires are locked together. Perfect for sand and loose dirt type conditions. The bad part about limited-slip diffs is that either there needs to be some actual slippage before they work, or they stop working if 1 tire totally give sup (helical cut limited slips are what come to mind for this) so you're already losing traction before it starts to rectify the situation. Lockers are there right from the start. Enjoyed the locker on my old 03 Toyota Tacoma and 10 F-150. Really handy on the dirt. Wish my current truck had that option, but it just has a regular torsen limited slip rear.